plant and animal organ system and their function

• Reproduction


  The biological process by which "offspring" are produced from their "parents"
• Types of reproduction


  • Sexual
  • Asexual
• Sexual reproduction


  • Involves the fusion of male and female gametes to form a zygote
  • The fusion of the nuclei of male and female gametes is known as fertilization
• Asexual reproduction


  • Does not involve gametes
  • Parts of a mature organism may develop into new individuals
• Sexual reproduction


  Requires 2 parent organisms
• Asexual reproduction


  Requires 1 parent organism
• Differences between plant and animal reproduction

  • Plants use bright colors to attract insects, animals use courtship pheromones and ultrasound
  • Plants have sex cells transmitted by a vector, animals have spermatozoa and oocyte meeting during sexual intercourse
  • Plants can reproduce asexually without gametes, animals can reproduce asexually
  • Plants reproduce sexually using male and female gametes forming a zygote, animals reproduce sexually
• Plant sexual reproduction


  1. Pollination - transfer of pollen from anther to stigma

  2. Self-pollination - pollen from one flower to stigma of same flower

  3. Cross-pollination - pollen from one flower to stigma of another flower of same species
• Plants do not have the ability to locomotion, so pollination is possible through various agents like birds, insects, and wind
• Types of plant asexual reproduction

  • Vegetative propagation - using vegetative tissues like stem, leaf, root
  • Apomixis
• Types of asexual reproduction

  • Binary fission - single parent cell divides into two daughter cells
  • Budding - parent cell produces bud, it gets detached and develops into new individual
  • Spore formation - reproduces by forming spores that develop into new individuals under favourable conditions
  • Fragmentation - organism with filamentous body breaks into fragments that each grow into a new individual
  • Regeneration - organism's body breaks up into parts that each develop into a new individual
  • Vegetative reproduction - organism produces new individuals from a vegetative part
• Stolon or runner


  A slender horizontal stem that runs along the ground. At the nodes, it forms adventitious roots and buds that grow into a new plant
• Plants with stolons or runners

  • Strawberry
  • Grass
• Bulb


  A short underground stem with fleshy leaf bases. The leaf bases contain food reserves to enable the plant to survive adverse weather conditions. At the center of the bulb is a vegetative growing point or an unexpanded flowering shoot
• Plants with bulbs


  • Lily
  • Onion
  • Tulip
• Rhizome


  A horizontal underground stem. Rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes
• Plants with rhizomes


  • Ginger
  • Bamboo
• Tuber


  An enlarged underground stem usually from rhizomes which serve as a storage organ for nutrients. Most tubers bear minute scale leaves, each with a bud that has the potential for developing into a new plant
• Plants with tubers


  • Potato
• Corm or bulbotuber


  A very short and vertical modified underground stem bearing membranous leaves and buds and acting as a vegetative reproductive structure
• Plants with corms or bulbotubers

  • Water chestnut
  • Gladiolus
• Sucker


  A plant that grows from the base of the root of the plant at a certain distance away from the plant
• Plants with suckers


  • Banana
• Artificial methods of asexual reproduction

  • Grafting
  • Cutting
  • Layering
  • Micropropagation
• Grafting


  A technique to produce plants whereby tissues of plants are joined to continue their growth together. The stem of the plant to be grafted is called scion, and the root is known as stock
• Cutting


  Growing a plant from a stem or root that has been cut from another plant. It is primarily used for more woody plants such as shrubs and bushes
• Layering


  A technique in which a stem attached to the plant is bent and covered with soil. The sharp bend will often induce rooting. This can be done on most plants with low-growing branches like climbing roses
• Micropropagation


  A rapid vegetative through tissue culture under laboratory conditions
• Apomixis


  Asexual reproduction where either the ovule or part of the ovary, which is diploid in nature, gives rise to a new seed without fertilization
• Sexual reproduction


  The production of genetically unique offspring by the union of sperm and egg nuclei to form a zygote
• Sexual reproduction


  1. Male gamete and female gamete union (fertilization)

  2. Zygote formation

  3. Embryo development

  4. Baby
• Fertilization can occur either outside the body or inside the body of the female
• In mammals, including humans, offspring are fertilized internally
• Mammals give birth to their young ones and are called viviparous
• In some amphibians and fishes, fertilization occurs outside of the female's body. They lay eggs and the offspring are hatched after being expelled from the body. They are called oviparous
• Some animals are ovoviviparous, where the fertilized eggs remain within the mother to complete the development
• Binary fission


  A form of asexual reproduction in which a parent cell divides into two or more genetically identical daughter cells
• Organisms that undergo binary fission

  • Amoeba
  • Paramecium
• Binary fission

  Mitosis
• Budding


  A form of asexual reproduction in which a new organism develops from the outgrowth (bud) of a part of a cell or body region leading to a separation from the original organism into two individuals